Upgrade FEZ watchface to SDK 2.0

I took the liberty of upgrading your code to SDK 2.0. Only minor changes, the biggest of which is using Pebble's "layer subclass" pattern, using layer_create_with_data's malloc capabilities to store the layer data inside the layer itself, rather than a PolyLayer struct containing a Layer. The extra fields in PolyLayer are now part of PolyLayerData, which is retrieved with ``layer_get_data(some_poly_layer)``, returning a void* pointer to the associated PolyLayerData.